Fernando Alonso's F1 future could be out of McLaren's hands

The Woking-based outfit is facing a race against time ahead of the season-opening Australian Grand Prix, with its Honda engine proving to be unreliable and down on power during pre-season testing.

After two already difficult seasons with McLaren, the current situation has prompted fresh speculation that Alonso could walk away if his frustrations get too much.

Alonso's contract runs out at the end of this year, and he has already indicated that he wants to stay in F1 for 2018.

McLaren racing director Eric Boullier has admitted that it is essential his team gives the Spanish driver a car that makes him 'happy', otherwise there is a chance he could give up on the project.

"There are always a lot of stories about this," Boullier said in an interview with Spanish newspaper AS about Alonso not staying at the team if the results are not good.

"Fernando is being honest with us, just as we're being honest with him.

"He first wanted to see how the new car was. And how the new regulations are. And I think he likes the new F1.

"He wants to be competitive because he has talent to show the world and to himself.

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"And we need to be competitive to keep him happy. If we're competitive he'll be happy and if not he'll take his own decisions..."

Boullier said he had already spoken to Alonso about next year, but said that it was "still early days" in terms of making any progress in those talks.

Although Alonso has not won a championship since 2006, Boullier says he has no doubts that he remains the best driver on the grid.

Pushed on why he believed that, Boullier said: "I don't want to give you too much information, because I know a lot of teams want that information, but he's the best.

"Without a doubt. He's the best because he is, clearly, but over and above that, it can be shown."